Opacity color

.opacity30 {
  opacity: 0.3;
  filter: alpha(opacity=30); /* For IE8 and earlier */
}

Css opacity background color

background: rgba(255, 255, 255, 0.25);

Background color with opacity

h1 {background-color:rgba(255,0,0,0.3);}

Background color opacity

rgba(51, 170, 51, .1)    /*  10% opaque green */ 
rgba(51, 170, 51, .4)    /*  40% opaque green */ 
rgba(51, 170, 51, .7)    /*  70% opaque green */ 
rgba(51, 170, 51,  1)    /* full opaque green */

Source: stackoverflow.com

Similar codes

6 votes339 views2 answers
Css border opacity
CSS
63 votes365 views5 answers
Html position absolute center
CSS
85 votes343 views5 answers
Scroll css
CSS
1 vote366 views1 answer
Css cursor size
CSS
0 vote350 views1 answer
Cop pics css
CSS
161 votes377 views6 answers
Css bold text
CSS
1 vote383 views2 answers
Absolute vertical position css
CSS
1 vote403 views2 answers
How to make hr class bootstrap full width
CSS Bootstrap
0 vote355 views1 answer
Inline styling width
CSS
3 votes328 views3 answers
How to center a html header
CSS